missing file: MFC42.dll:6547

The answer could depend on what programs are causing you problems. There is a Microsoft article on how to restore files. Look especially at step 7, where MFC42 is mentioned.
(Type the following in the address box of Internet Explorer)

MSKB Q246466

Encarta can have this problem; Money can as well. Please provide more details, or go to
http://search.microsoft.com and enter MFC42

A number of programs is linked to MFC42.dll
Ref.microsoft knowlegebase articles Q195801 or Q184799
Other options to restore file
1)Use System File Checker Tool to extract from the operating system disk
Click Start->Run->type sfc.exe in the box and click OK
2)To update the library file
Windows Updates
Go to www.microsoft.com/downloads/search.asp?
Windows Libraries Update
In Search area click Keywords
In Keyword box,type libraries update
In operating system box,click the appropiate OS,then click find it
Click on Link rendered and follow the onscreen instructions to extract and install

Go to driverguide.com, login is drivers and password is all. Go to the .dll section, and find your .dll file. Note: you have to have the version number listed on the end.

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